The history of computing architectures is one of exceptional and rapid advance. Indeed, the development of ubiquitous, flexible, low cost computing platforms is arguably one of the most important engineering feats of the last thirty years. It has also fundamentally changed the way in which many organizations operate.
Particular developments in communications technology over the last several years have produced an environment where many people require access to information in various forms stored in computing systems. Indeed, the need to efficiently store the virtual torrents of information that move in and out of today's business computing systems was not expected when the first computing systems and certainly the first low cost personal computer systems were first placed on the desk top.
Initially, computing system architectures for the desktop required only enough local storage capacity for application programs and data generated by individuals. A direct-attached architecture whereby storage devices such as Hard Disk Drives (HDDs) were directly connected to internal computing system such as the Advanced Technology (AT) bus was quite adequate for these needs. Organizations and their information technology departments later found it advantageous to adopt a client server model where centralized server processors manage access to relatively large centralized storage arrays. This architecture continues to use the direct-attached storage model. To achieve higher performance, most servers attached multiple HDDs using a high speed bus such as Small Computer System Interface (SCSI). The SCSI interface requires a host adapter circuit board to connect to a PC, but as a single SCSI adapter can manage up to eight units or “identifiers.” Since the host adapter uses one of these identifiers, seven other identifiers may be used for additional hardware peripherals such as Hard Disk Drives, tape drives, CD-ROMs, scanners, and the like.
Despite the development of a higher speed SCSI-2 interface in the 1990s, the most widely used interface between a storage device and the processor is still the so-called “Integrated Device Electronics (IDE), or more properly the AT Attachment (or ATA)-type interface. ATA type disk drives have the drive controller built into them. They simply plug into a connector on a PC motherboard or to an AT interface adapter card. Such drives are thus quite easy to install and require a minimum number of cables given that the controller is located on the drive itself.
Because the proper controller is integrated with the disk drive itself, ATA/IDE drives are much easier for system manufacturers to configure. This has been perhaps a downfall of the SCSI interface which lacks a standard controller interface. In particular, each device's PC manufacturer seems to have its own idea of how the SCSI interface should work. While the physical connections themselves have been standardized, actual driver specifications used for communication among devices has not. The end result is that each bit of SCSI hardware typically requires its own host adapter, and the software drivers for that device typically are incompatible with adapters and drives made by other manufacturers. Because of these aforementioned difficulties, it can be cumbersome to configure arrays of SCSI based storage devices to work well with a variety of different computing platforms.
Certain other devices, such as the Kanguru™ family of storage products available from Interactive Media Corporation, provide a device that is a removable hard disk having an interface that permits it to be used both as an internal and external device. This device can provide some flexibility in making data available to multiple users and locations.
The evolution of demands on direct-attached storage architectures has also resulted in the development of additional storage initiatives. Thanks in large part to increasing use of the Internet, data is created, transmitted, stored and delivered in numerous places in an organization's computing environment. Businesses need to meet skyrocketing storage needs without an exponential increase in the required information technology personnel support and/or equipment costs.
Network Attached Storage (NAS) is yet another solution to the storage problem. This concept allows for shared use storage device that is connected to a computer network. An NAS device is typically a dedicated, high performance, high speed computing device that is optimized to stand alone and serve specific storage access needs. Its file systems are typically compatible with networking protocols such as Microsoft Windows™ environments, FTP, HTTP, and the like. The idea basically is to provide a file server having network protocol capability. This permits any other machine also connected to the network to access files and other information stored on the network attached drives.
However, even with network attached storage, there are performance penalties given that data to be transferred must be packaged according to network protocols. The networking devices themselves have inherent speed limitations as compared to directly attached storage architectures.
In addition, network attached disks can require Information Technology personnel to set up network protocols. It would be preferred if a simply plug and play-type universal interface could be used.